Reviews by patients who have Tooth Pain and take Zinc either as part of daily diet or as method of treatment. Positive and negative experiences from patients with Tooth Pain that take Zinc
1 Red or black colored stool may be a sign of bleeding in the GI tract (from the esophagus, stomach, small intestine or colon) and should not be ignored.  When stool color changes, what tests need to be done depend upon depends upon what cause is suspected for the stool color change.
So knowing what causes black stool is important to ease your worries, or get you to the doctor -- stat! Bleeding that happens in the esophagus, stomach, or the first part of the small intestine is the most common cause of a stool that appears black or tarry, according to the National Institutes of Health. Bleeding in the upper part of the gastro-intestinal, or GI, tract will usually cause black stools due to: